The reason copper is a better and best conductor of electricity is because coppers molecular structure and metallic band, Electron concentration and mobility in the copper is very high.
This helps the electricity flow much more freely through the copper metal wire than it would through steel, aluminum etc.
When it comes to conducting electricity the copper wire is the much better conductor of electricity than aluminum.
Aluminum is a good conductor of electricity but copper is a much better conductor of electricity and it's used a lot more than aluminum.
Copper and Aluminum are good conductors of electricity.
However copper is a much better conductor of electricity and copper can carry more current on a smaller wire size than aluminum.
You need larger aluminum wire to carry the same amount of electricity as a smaller copper wire can carry.
Copper is mostly used as current conductors in wires, electric motors, inside houses, buildings etc as it carries the current much better than aluminum.
Copper does carry more current than aluminum and copper can carry more current with a smaller size wire than aluminum can with a larger size wire.
You can use smaller size copper wire to carry more current than you could with a larger size aluminum wire.
Aluminum wire is cheaper and lighter than copper wire and for overhead and underground service wire from the pole or transformer to your house the utility uses mostly aluminum wire.
That is because aluminum is cheaper than copper.
However some people will use copper wire from the weather head or meter box to the inside of the house.
Copper wire is also easier to work with and bend than aluminum wire and it lasts longer and doe snot oxidize like aluminum wire can.
Copper wire is always used inside the house because it's safer than aluminum and does not fall apart as easily and start fires.